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At what body weight is 7/64 Amsteel not enough?

Hi all,

My ENO DoubleNest is coming in tomorrow and I was thinking about heading to West Marine to pickup some Amsteel and make some whoopie slings. Then I remembered reading about all of the angles and weights suspension systems can see and it made me wonder... is 7/64 enough? At what body weight, if any, should I use 1/8 instead?

We have done 24 hour continuous dynamic load testing to 600 pounds on 7/64 in house. Another vendor has had lab testing done to breaking point, failure was at full rating. Unless your going to host a small party in your hammock, you know with a band, 3 kegs, those what's up guys from 2004.........Sorry its getting late and dis not sleep well last night.......You will be fine with 7/64.

Do a bit of search on engineering safety margins for cordage. IMO, Sgt is being liberal. A margin of 5 to 1 is for non-human support, so 5 to 1 will be the ratio of strength to maximum working load for such as tow ropes and straps. 10-15 to 1 is the safety margin for human loads.

On the other hand, and it is a strong hand.

The load is almost shared by two cords, each bearing about half the weight.

Engineering conservatism appropriately assumes that the cord will be terminated in knots which will compromise the strength by 40-60%. On average ,then, there's a need for cord that is twice as strong as its maximum expected static load. However, and in contrast, you will find in HF everywhere, descriptions of proper splicing methods for (hollow braid) Amsteel, which result in no more than a 10% strength loss from terminations. So, that source of risk to safety is minimized. Further, IIANM, the rating on Amsteel from Sampson Rope is already of a properly spliced line.

Do a bit of search on engineering safety margins for cordage. IMO, Sgt is being liberal. A margin of 5 to 1 is for non-human support, so it 5 to 1will be the ratio of strength to maximum working load for such as tow ropes and straps.

On the other hand, and it is a strong hand.

The load is almost shared by two cords, each bearing about half the weight.

Engineering conservatism appropriately assumes that the cord will be terminated in knots which will compromise the strength by 40-60%. On average ,then, there's a need for cord that is twice as strong as its maximum expected static load. However, and in contrast, you will find in HF everywhere, descriptions of proper splicing methods for (hollow braid) Amsteel, which result in no more than a 10% strength loss from terminations. So, that source of risk to safety is minimized. Further, IIANM, the rating on Amsteel from Sampson Rope is already of a properly spliced line.

Not to be too picky but anywhere I was involved the safety rating would be 5x the derated limit. In other words if the knot used created a 60% loss in strength 1600 lb amsteel with that knot would be 1600 x 0.4 /5= 128 lbs. That is why one does not replace splices with knots. ;-)